Old person smell
{{short description|Odor of elderly humans}}
{{Use dmy dates|date=January 2023}}
Old person smell is the characteristic odor of elderly humans.{{Cite magazine |last=Sifferlin |first=Alexandra |date=31 May 2012 |title='Old-Person Smell' Really Exists, Scientists Say |url=https://healthland.time.com/2012/05/31/old-person-smell-really-exists-scientists-say/ |url-status=live |magazine=Time |access-date=10 February 2016 |archive-url=https://web.archive.org/web/20150704160359/http://healthland.time.com/2012/05/31/old-person-smell-really-exists-scientists-say |archive-date=4 July 2015}} Like many other animal species, human odor undergoes distinct stages based on chemical changes initiated through the aging process. Research suggests that this enables humans to determine the suitability of potential partners based on age, in addition to other factors.{{Cite journal |last1=Mitro |first1=Susanna |last2=Gordon |first2=Amy R. |last3=Olsson |first3=Mats J. |last4=Lundström |first4=Johan N. |date=30 May 2012 |title=The Smell of Age: Perception and Discrimination of Body Odors of Different Ages |journal=PLOS ONE |volume=7 |issue=5 |pages=e38110 |bibcode=2012PLoSO...738110M |doi=10.1371/journal.pone.0038110 |pmc=3364187 |pmid=22666457 |doi-access=free}}
Biology
One study suggested that old person smell may be the result of 2-nonenal, an unsaturated aldehyde which is associated with human body odor alterations during aging.{{Cite journal |last1=Haze |first1=S. |last2=Gozu |first2=Y. |last3=Nakamura |first3=S. |last4=Kohno |first4=Y. |last5=Sawano |first5=K. |last6=Ohta |first6=H. |last7=Yamazaki |first7=K. |year=2001 |title=2-Nonenal Newly Found in Human Body Odor Tends to Increase with Aging |journal=Journal of Investigative Dermatology |volume=116 |issue=4 |pages=520–4 |doi=10.1046/j.0022-202x.2001.01287.x |pmid=11286617 |doi-access=free}} Another study failed to detect 2-nonenal at all, but found significantly increased concentrations of benzothiazole, dimethylsulphone, and nonanal on older subjects.{{Cite journal |last1=Gallagher |first1=M. |last2=Wysocki |first2=C.J. |last3=Leyden |first3=J.J. |last4=Spielman |first4=A.I. |last5=Sun |first5=X. |last6=Preti |first6=G. |date=October 2008 |title=Analyses of volatile organic compounds from human skin |journal=British Journal of Dermatology |volume=159 |issue=4 |pages=780–791 |doi=10.1111/j.1365-2133.2008.08748.x |pmc=2574753 |pmid=18637798}} There are also other hypotheses,{{Cite web |last=MacMillan |first=Amanda |title=Scientists Confirm Existence of 'Old Person Smell' |url=http://news.health.com/2012/05/30/old-person-smell/ |url-status=live |archive-url=https://web.archive.org/web/20150908030246/http://news.health.com/2012/05/30/old-person-smell/ |archive-date=8 September 2015 |access-date=30 May 2012 |website=Health.com |publisher=Health Media Ventures, Inc.}} such as change of the monounsaturated fatty acid composition of skin surface lipids and the increase of lipid peroxides associated with aging.{{cite journal |doi=10.1113/jphysiol.2001.013067 |title=The cutaneous uptake of atmospheric oxygen contributes significantly to the oxygen supply of human dermis and epidermis |date=2002 |last1=Stücker |first1=M. |last2=Struk |first2=A. |last3=Altmeyer |first3=P. |last4=Herde |first4=M. |last5=Baumgärtl |first5=H. |last6=Lübbers |first6=D. W. |journal=The Journal of Physiology |volume=538 |issue=3 |pages=985–994 |pmid=11826181 |pmc=2290093 }}
In 2012, the Monell Chemical Senses Center published a press release claiming that the human ability to identify information such as age, illness, and genetic suitability from odor is responsible for the distinctive "old man smell". Sensory neuroscientist Johan Lundström stated, "Elderly people have a discernible underarm odor that younger people consider to be fairly neutral and not very unpleasant."{{Cite press release |publisher=Monell Chemical Senses Center |date=30 May 2012 |title=The special scent of age |url=http://www.eurekalert.org/pub_releases/2012-05/mcsc-tss052412.php |url-status=live |archive-url=https://web.archive.org/web/20150620161908/http://www.eurekalert.org/pub_releases/2012-05/mcsc-tss052412.php |archive-date=20 June 2015 |website=EurekAlert!}}
In Japan
{{See|Aging of Japan}}
Old person smell is known as {{nihongo||加齢臭|kareishū}} in Japan, where much social value is placed on personal grooming, and specific upmarket odor-eliminating soaps are targeted at more elderly consumers.{{Cite web |last=Levenstein |first=Steve |date=6 August 2008 |title=Japan's Aging Population Deals with Old Man Smell |url=http://inventorspot.com/articles/japans_aging_population_deals_with_old_man_smell_16746 |archive-url=https://web.archive.org/web/20150906044247/http://inventorspot.com/articles/japans_aging_population_deals_with_old_man_smell_16746 |archive-date=6 September 2015 |website=Inventor Spot |publisher=Halcyon Solutions Inc.}}